Every year the same bad advice gets recycled: “Stop feeding your koi in the fall or the food will rot in their gut and kill them.”
That’s a myth and it’s costing people fish.
Here’s the truth:
Koi don’t suddenly lose the ability to digest food when the water cools. Their metabolism slows, yes but it doesn’t stop.
When you stop feeding too early, you rob your koi of the energy reserves they need to make it through winter.
The real danger isn’t fall feeding — it’s spring stress. Fish weakened by months of undernourishment are the first to crash when parasites and bacteria wake up.
I’ve seen it too many times: koi starved all winter, then dead in March or April. Not because they were “fed in cold water” — but because they weren’t fed at all.
Feed appropriately for the temperature, use a quality food, and give them what they need to carry their weight through winter.
Your koi are more likely to die in the spring from being underfed in the fall than from any food you responsibly give them now.
Stop following myths. Start following biology. Feed your koi.
Written by Jason Michael, a 30-year aquaculture professional with experience in commercial koi farming and fish health management.
